Air purifiers have become a very important appliance in many houses, hospitals, schools and offices located in cities with high pollution levels.
And researchers at IIT-Madras have come up with one that is both affordable and efficient.
S M Shiva Nagendra, Associate professor in the Department of Environmental and Water Resources Engineering at IIT-M, along with a few other research scholars, had been working on this purifier for the last three years. They are members of Air OK Technologies, a faculty startup launched under the IIT-M incubation cell.
The device is a sensor-based indoor air purifier meant to reduce the pollutant load in a room. As it is made of low-cost materials, the product will be a reasonably priced alternative to air purifiers that are currently available at a cost of Rs. 15,000 and more. The team has not finalised the price as of now, and the purifier will be soon commercialised.
It has a cylindrical body made of stainless steel and it works with a three-layer technology. A fan fitted at the bottom of the body sucks in the air whenever the sensor detects pollutants. This air then passes through a filter that has the following layers:
1. The filter is basically a muslin fabric bag. This fabric first pre-filters the air and removes large particles like dust.
2. After this, the air passes through a thick layer of charcoal that the bag is filled with. This layer absorbs pollutants like chemicals and other microscopic particles. Charcoal has a high surface area that gives it a lot of bonding places and the pollutants stick to its pores.
3. The final layer is an ultraviolet light fixed above the charcoal layer. This light treats bacteria and viruses.
“We spend a lot of time indoors. While pollutants outdoors move around, in rooms they get accumulated and keep circulating,” Shiva Nagendra, who has been studying air pollution for almost 15 years now, told The Times of India.
Once it is available in the market, the device will be useful for people with asthma and other respiratory diseases. It can also be used in hospitals that need a sterilised environment, and in other buildings located in polluted areas.